Re: git: network - Move socket from netmsg ext to netmsg header,
:...
:+#endif /* INET6 */
:+ error = tcp_connect(tp, flags, m, nam, td);
:+#if 0
:+ /* WTF is this doing here? */
:+ tp->snd_wnd = TTCP_CLIENT_SND_WND;
:+ tcp_mss(tp, -1);
:+#endif
:+ goto out;
:+ }
:
:Those lines are there for T/TCP support. When using T/TCP, you send the
:data in the SYN packet so you don't have any window information from the
:server. RFC1644 suggests using a 4K window by default. Similarly, the -1
:...
:Given that pretty much nobody uses T/TCP (Linux doesn't even implement
:it) I'd suggest we remove it altogether. Otherwise, we should revert at
:least the change above (of course, I would not be surprised if T/TCP has
:been broken for years and nobody noticed ;)
:
:Aggelos
I'd say remove it alltogether. The problem with reverting the change
is that the MSS code #if 0'd out above is not really compatible
with the the MSS tcp option, and the unconditional snd_wnd update
seems to override more appropriate defaults (at least during my testing)
set prior to the code hitting that point.
T/TCP doesn't work well with the syncache, opens us up to DOS attacks
(holding bulk data before the handshake sequence is complete), but the
biggest problem I had when I was doing that work was that the data has
to be forwarded to the protocol thread on the correct port in some other
piece of code... I forget exactly which piece of code it was but it was
a real mess to deal with.
-Matt
Matthew Dillon
<dillon@backplane.com>
討論串 (同標題文章)
完整討論串 (本文為第 6 之 11 篇)：